JP2004352730A - Polyimide resin composition and resin sheet - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a polyimide resin composition which can satisfy both a low water absorption ratio and a low thermal expansion ratio, and a resin sheet. <P>SOLUTION: The polyimide resin composition comprises a polyimide resin and, contained therein, a layered silicate salt swollen with an intercalated organic compound, and has a tanδ peak temperature falling within the temperature range from 0°C to the glass transition temperature of the polyimide resin and at least 30°C higher than the tanδ peak temperature of the polyimide resin in the dynamic viscoelasticity measurement by tensile shear stress. The resin sheet is comprised of the polyimide resin composition. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

【０１０１】
【発明の効果】
本発明のポリイミド樹脂組成物は、低い吸水率と低い熱膨張率に優れているため、絶縁性の低下や熱膨張による断線等を妨げることができるので、高い接続信頼性を発揮することができる。
また、本発明の基板用材料は、本発明のポリイミド樹脂組成物から構成されているので、低い吸水率と低い熱膨張率に優れており、絶縁性の低下や熱膨張による断線等を妨げることができるため、高い接続信頼性を発揮することができる。[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a polyimide resin composition and a resin sheet having excellent low water absorption and low thermal expansion coefficient.
[0002]
[Prior art]
In general, polyimide resin is excellent in insulation, heat resistance and elasticity, and is used for a material for a wiring board such as a multilayer printed board and a build-up board, a sealing film, etc. With the recent increase in density and thinning of electronic devices, higher connection reliability is required for polyimide resins.
[0003]
In addition, wiring boards used for general communication and vehicles are often used under severe environments such as high temperature and high humidity. In addition, the polyimide resin has high water absorption, and when a wiring board having an insulating layer made of the polyimide resin is used under such a high-temperature and high-humidity environment, the polyimide resin absorbs water in the air and the insulating property is reduced. As a result, there is a problem that the connection reliability is reduced.
[0004]
However, when a resin having a high coefficient of thermal expansion such as a polyimide resin is used as a material for the substrate, the wiring substrate is heated and expanded by the operation of the wiring substrate, thereby causing a short circuit or disconnection, thereby lowering connection reliability. There was a problem.
In particular, in recent wiring boards, thin metal wirings are provided at narrow intervals, so that short-circuiting or disconnection is likely to occur due to thermal expansion. Therefore, as a substrate material used for wiring boards, it has a low coefficient of thermal expansion. There is a need for a resin composition.
[0005]
Therefore, in order to solve these problems, a polyimide resin composition in which an organic onium ion and a layered clay mineral are added to a polyimide resin is disclosed, and the layered silicate is dispersed in the polyimide resin composition. It has been reported that both a low water absorption and a low coefficient of thermal expansion could be achieved (for example, Patent Document 1).
[0006]
[Patent Document 1]
Japanese Patent No. 2872756
[0007]
[Problems to be solved by the invention]
However, in the above polyimide resin composition, since the layered silicate may not be dispersed in a sufficiently fine state, it is difficult to reliably achieve both a low water absorption and a low coefficient of thermal expansion. There was a problem.
[0008]
In view of the above problems, an object of the present invention is to provide a polyimide resin composition and a resin sheet that can achieve both a low water absorption and a low coefficient of thermal expansion.
[0009]
[Means to solve the problem]
In order to solve the above problem, the invention according to claim 1 is a polyimide resin composition containing a layered silicate swollen with an interlayer organic compound in a polyimide resin, wherein the polyimide resin composition is subjected to tensile shearing. The peak temperature of tan δ in the dynamic viscoelasticity measurement due to stress is in a temperature range from 0 ° C. to the glass transition temperature of the polyimide resin, and is a temperature 30 ° C. or more higher than the peak temperature of tan δ of the polyimide resin. The polyimide resin composition is characterized in that:
[0010]
The invention according to claim 2 is a polyimide resin composition containing a layered silicate swollen with an interlayer organic compound in a polyimide resin, wherein the polyimide resin composition has a dynamic viscosity due to tensile shear stress. The polyimide has a peak temperature of tan δ in elasticity measurement in a temperature range from 0 ° C. to a glass transition temperature of the polyimide resin or lower, and is at least 1.2 times the tan δ peak temperature of the polyimide resin. It is a resin composition.
[0011]
The invention according to claim 3 is a polyimide resin composition containing a layered silicate swollen by an interlayer organic compound in a polyimide resin, wherein the polyimide resin composition has a dynamic viscosity due to a tensile shear stress. The tan δ peak temperature in the elasticity measurement is in the temperature range from 0 ° C. to the glass transition temperature of the polyimide resin, and the tan δ peak intensity of the polyimide resin composition is 0% of the tan δ peak intensity of the polyimide resin. 0.7 times or less.
[0012]
According to a fourth aspect of the present invention, there is provided the polyimide resin composition according to any one of the first to third aspects, wherein the polyimide resin has thermoplasticity.
[0013]
The invention according to claim 5 is characterized in that the layered silicate is at least one selected from montmorillonite, hectorite, saponite, swellable mica, and vermiculite. The polyimide resin composition according to item 1 is provided.
[0014]
According to a sixth aspect of the present invention, there is provided a resin sheet comprising the polyimide resin composition according to any one of the first to fifth aspects.
[0015]
Hereinafter, the present invention will be described in detail.
The polyimide resin composition of the present invention is formed of a polyimide resin and a layered silicate.
[0016]
As the polyimide resin forming the polyimide resin composition, for example, a resin containing dianhydrides, diamines or the like as a monomer or an oligomer is exemplified. These polyimide resins may be used alone or in combination of two or more.
[0017]
Examples of dianhydrides include pyromellitic anhydride, 3,3 ′, 4,4′-benzophenonetetracarboxylic dianhydride, 3,3 ′, 4,4′-diphenylsulfonetetracarboxylic dianhydride, 3,3 ′, 4,4′-diphenylethertetracarboxylic dianhydride and the like.
[0018]
Examples of the diamines include bis [4- (3-aminophenoxy) phenyl] sulfone, 1,3-bis (4-aminophenoxy) benzene, 4,4′-diaminodiphenyl ether, 1,4-diaminobenzene, and the like. No.
[0019]
Further, the polyimide resin is preferably thermoplastic. When the polyimide resin is thermoplastic, the polyimide resin composition of the present invention can exhibit high moldability.
[0020]
Further, the molecular weight of the oligomer or polymer constituting the polyimide resin is preferably 4,000 to 100,000. Thereby, the polyimide resin composition of the present invention can exhibit high moldability.
[0021]
The polyimide resin composition of the present invention contains a layered silicate swollen with an interlayer organic compound.
In the present specification, the layered silicate means a mineral constituting a main component of clay, and specifically, a swellable layered silicate mineral having exchangeable exchangeable metal cations between layers. means. This layered silicate may be a natural product or a synthetic product.
[0022]
The exchangeable metal cation present between the layers of the layered silicate means metal ions such as sodium and calcium present on the surface of the flaky crystal of the layered silicate. Since these metal ions have cation exchange properties with a cationic substance, various cationic substances can be inserted between the crystal layers of the layered silicate.
[0023]
The cation exchange capacity of the layered silicate is not particularly limited, but is preferably 50 to 200 milliequivalents / 100 g.
If the cation exchange capacity is less than 50 milliequivalents / 100 g, the amount of the cationic substance inserted between the layers of the layered silicate by the cation exchange decreases, so that the crystal layers are sufficiently depolarized (hydrophobicized). Instead, the affinity with the polyimide resin is reduced. On the other hand, if the cation exchange capacity exceeds 200 milliequivalents / 100 g, the bonding strength between the crystal layers of the layered silicate becomes too strong, and it becomes difficult to peel the flaky crystal of the layered silicate.
[0024]
The layered silicate preferably contains 2 to 50 parts by weight, more preferably 5 to 30 parts by weight, and more preferably 5 to 10 parts by weight, based on 100 parts by weight of the polyimide resin composition. Is more preferred. Thereby, the polyimide resin composition of the present invention can exhibit a low water absorption and a low coefficient of thermal expansion. Further, it is also possible to prevent a decrease in mechanical strength of the polyimide resin composition after drying.
[0025]
When the content of the layered silicate is less than 2 parts by weight, it is difficult to exhibit a low coefficient of thermal expansion in the polyimide resin composition, and when the content of the layered silicate exceeds 50 parts by weight, the specific gravity increases and The resin composition becomes brittle.
[0026]
Further, the layered silicate preferably has a large shape anisotropy effect defined by the following formula (1). By using a layered silicate having a large shape anisotropy effect, the polyimide resin composition of the present invention can have excellent mechanical properties.
[0027]
Shape anisotropy effect = surface area of flaky crystal lamination surface / surface area of flaky crystal lamination side surface
[0028]
Examples of such a layered silicate include smectite, swellable mica, vermiculite, halloysite, and the like. Examples of the smectite include montmorillonite, hectorite, saponite, beidellite, stevensite, nontronite and the like.
Of these, montmorillonite, hectorite, saponite, swellable mica, and vermiculite are preferably used as the layered silicate. These layered silicates may be used alone or in combination of two or more.
[0029]
The polyimide resin composition of the present invention preferably has a sufficiently large interface area between the polyimide resin and the layered silicate. Thereby, the interaction between the polyimide resin and the surface of the layered silicate is increased, so that the melt viscosity of the polyimide resin composition is increased and the moldability can be improved.
[0030]
It is preferable that the layered silicate is uniformly dispersed in the polyimide resin, and it is more preferable that the layered silicate is finely dispersed in the polyimide resin. The layered silicate is uniformly dispersed in the polyimide resin, or is dispersed in a fine state in the polyimide resin, whereby the molecular chain motion of the polyimide resin is sterically constrained, resulting in a low coefficient of thermal expansion and low water absorption. Can be demonstrated.
Further, since the layered silicate is dispersed as flaky crystals having a predetermined number of layers, the physical strength of the polyimide resin composition of the present invention can be increased, and the polyimide resin composition is processed into a thin sheet or the like. Even high physical strength can be exhibited. Further, the distance between the dispersed layered silicates is preferably an appropriate distance.
[0031]
Examples of the method of dispersing the layered silicate in the polyimide resin include a method using an organic layered silicate, a method using a foaming agent, a method using a dispersant, and the like. By using these methods, the layered silicate can be more uniformly and finely dispersed in the polyimide resin.
[0032]
As a method of using an organically modified layered silicate which is one of the methods for dispersing the layered silicate, a method of using an organically modified layered silicate in which the interlayer is swollen by the following swelling methods (1) to (6) is exemplified. Can be These swelling methods may be used alone or in combination of two or more.
The term "organized layered silicate" refers to a layered silicate swollen by interlayer organic compounds between layers of the layered silicate.
[0033]
The swelling method (1) is a method also called a cation exchange method using an interlayer organic compound. Specifically, the interlayer of the layered silicate is swelled in advance by cation exchange between the layers of the layered silicate using the interlayer organic compound. This is a method of making the surface hydrophobic. Since the affinity between the layered silicate and the polyimide resin is increased by making the layers of the layered silicate hydrophobic in advance, the layered silicate can be dispersed in a more uniform and fine state.
[0034]
Such an interlayer organic compound is not particularly limited, and examples thereof include quaternary ammonium salts and quaternary phosphonium salts.
Among such quaternary ammonium salts, quaternary ammonium salts having an alkyl chain having 6 or more carbon atoms, aromatic quaternary ammonium salts, and heterocyclic quaternary ammonium salts can sufficiently swell between the crystal layers of the layered silicate. Is preferably used.
[0035]
Examples of the quaternary ammonium salt include trioctylmethyl ammonium salt, lauryl trimethyl ammonium salt, stearyl trimethyl ammonium salt, distearyl dimethyl ammonium salt, di-hardened tallow dimethyl ammonium salt, distearyl dibenzyl ammonium salt, N-polyoxy Ethylene-N-lauryl-N, N-dimethylammonium salt, trimethylalkylammonium salt, triethylalkylammonium salt, tributylalkylammonium salt, dimethyldialkylammonium salt, dibutyldialkylammonium salt, methylbenzyldialkylammonium salt, dibenzyldialkylammonium salt , Trialkylmethylammonium salt, trialkylethylammonium salt, trialkylbutylammonium Quaternary ammonium salts having an aromatic ring such as benzylmethyl {2- [2- (p-1,1,3,3-tetramethylbutylphenoxy) ethoxy] ethyl} ammonium chloride; aromatics such as trimethylphenylammonium Quaternary ammonium salts having an amine; quaternary ammonium salts having a heterocyclic ring, such as alkylpyridinium salts and imidazolium salts; dialkyl quaternary ammonium salts having two polyethylene glycol chains, and dialkyl quaternary ammonium salts having two polypropylene glycol chains Salts, trialkyl quaternary ammonium salts having one polyethylene glycol chain, and trialkyl quaternary ammonium salts having one polypropylene glycol chain.
[0036]
Among these quaternary ammonium salts, quaternary ammonium salts having a heterocyclic ring such as imidazolium salts, lauryl trimethyl ammonium salt, stearyl trimethyl ammonium salt, trioctyl methyl ammonium salt, distearyl dimethyl ammonium salt, and di-hardened tallow dimethyl ammonium Salt, distearyldibenzylammonium salt, N-polyoxyethylene-N-lauryl-N, N-dimethylammonium salt and the like are preferably used.
[0037]
Further, among these quaternary ammonium salts, a heterocyclic quaternary ammonium salt having a heterocyclic ring such as an imidazolium salt is more preferably used. By swelling the interlayer of the layered silicate using the heterocyclic quaternary ammonium salt, the dispersibility of the layered silicate in the polyimide resin can be further improved.
Examples of the imidazolium salt include 1,2-dimethyl-N-decylimidazolium, 1,2-dimethyl-N-octylimidazolium, 1,2-dimethyl-N-butylimidazolium, and the like.
[0038]
In the swelling method (2), a functional group capable of chemically bonding to the hydroxyl group or a chemical group of the hydroxyl group present on the crystal surface of the organically modified layered silicate swollen between layers by the swelling method (1) is used. This is a method of further swelling using a compound having one or more functional groups having high affinity at the molecular terminals.
[0039]
Examples of a functional group capable of chemically bonding to a hydroxyl group or a functional group having a high chemical affinity with a hydroxyl group include, for example, an alkoxy group, a glycidyl group, a carboxyl group (including a dibasic acid anhydride), a hydroxyl group, and an isocyanate group. And aldehyde groups.
Examples of compounds having these functional groups include silane compounds, titanate compounds, glycidyl compounds, carboxylic acids, and alcohols having these functional groups. These compounds may be used alone or in combination of two or more.
[0040]
The silane compound having these functional groups is not particularly limited, and examples thereof include vinyltrimethoxysilane, vinyltriethoxysilane, vinyltris (β-methoxyethoxy) silane, γ-aminopropyltrimethoxysilane, and γ-aminopropylmethyldimethoxy. Silane, γ-aminopropyldimethylmethoxysilane, γ-aminopropyltriethoxysilane, γ-aminopropylmethyldiethoxysilane, γ-aminopropyldimethylethoxysilane, methyltriethoxysilane, dimethyldimethoxysilane, trimethylmethoxysilane, hexyltri Methoxysilane, hexyltriethoxysilane, N-β- (aminoethyl) γ-aminopropyltrimethoxysilane, N-β- (aminoethyl) γ-aminopropyltriethoxysilane, N-β- ( Minoethyl) γ-aminopropylmethyldimethoxysilane, octadecyltrimethoxysilane, octadecyltriethoxysilane, γ-methacryloxypropylmethyldimethoxysilane, γ-methacryloxypropylmethyldiethoxysilane, γ-methacryloxypropyltrimethoxysilane, γ- Methacryloxypropyltriethoxysilane and the like can be mentioned. These silane compounds may be used alone or in combination of two or more.
[0041]
The swelling method (3) includes a functional group capable of chemically bonding with the hydroxyl group or a chemical affinity with the hydroxyl group present on the crystal surface of the crystallized layered silicate swollen between layers by the swelling method (1). This is a method of further swelling using a highly functional functional group and a compound having one or more reactive functional groups at the molecular terminals.
[0042]
The swelling method (4) is a method of further swelling the crystallized surface of the organically modified layered silicate which has been swollen between layers by the swelling method (1), using a compound having anionic surface activity.
The compound having such an anionic surfactant is not particularly limited as long as it can swell between the layers of the layered silicate by ionic interaction. For example, sodium laurate, sodium stearate, sodium oleate, higher alcohols Sulfate, secondary higher alcohol sulfate, unsaturated alcohol sulfate, and the like. These compounds may be used alone or in combination of two or more.
[0043]
In the swelling method (5), the compound having an anionic surface activity is reactive with the crystal surface of the organically modified layered silicate swollen between the layers by the swelling method (1), except for the anion site in the molecular chain. This is a method of further swelling using a compound having one or more functional groups.
[0044]
In the swelling method (6), a resin having a functional group capable of reacting with the layered silicate is added to the organically modified layered silicate swollen between layers by any one of the swelling methods (1) to (5). It is a method of adding and further swelling.
[0045]
A method using a foaming agent, which is one of the methods for dispersing the layered silicate, is to foam the polyimide resin using a foaming agent in a mixed state of the polyimide resin and the layered silicate, and to increase the foaming energy by the dispersion energy of the layered silicate. It is a way to convert to. Examples of such a foaming agent include a gaseous foaming agent, a volatile liquid foaming agent, and a heat decomposition type solid foaming agent. These foaming agents may be used alone or in combination of two or more.
As a method using a blowing agent, for example, after impregnating a gaseous blowing agent under high pressure with respect to a mixed state of a polyimide resin and a layered silicate, a method of foaming the gaseous blowing agent, A method in which a heat-decomposable foaming agent is previously contained between the layers, and the heat-decomposable foaming agent is decomposed by heating to foam.
[0046]
The crystal shape of the layered silicate when dispersed is not particularly limited, but the average length of one side of the surface portion is preferably 0.01 to 3 μm, and more preferably 0.05 to 2 μm.
[0047]
Further, the average thickness of the layered silicate is preferably 0.001 to 1 μm, more preferably 0.01 to 0.5 μm.
Here, the crystal shape of the layered silicate is measured by observing a cross section of the polyimide resin composition with an electron microscope or the like.
[0048]
The number of layers of the layered silicate dispersed in the polyimide resin composition is preferably 5 or less, more preferably 3 or less, and even more preferably 1 layer. By dispersing the layered silicate in the polyimide resin composition in five or less layers, the interface area between the polyimide resin and the layered silicate can be further increased.
Note that a laminate having five or less layers specifically means a state in which the number of flaky crystals is five or less because the interaction between the flaky crystals of the layered silicate is weakened.
[0049]
Further, the proportion of the layered silicate having five or less layers dispersed in the polyimide resin composition is preferably 10% or more, and more preferably 20% or more. If the ratio of the layered silicate in the resin composition is less than 10%, the strength of the resin composition may be reduced.
Here, the ratio Z of the layered silicate dispersed as a laminate of 5 layers or less was observed by magnifying the polyimide resin composition of the present invention 50,000 to 100,000 times with a transmission electron microscope. Calculated from the following equation (2) by measuring the total number X of layered silicate laminates observable in a fixed area and the number Y of layered laminates dispersed as a laminate of 5 or less layers. can do.
[0050]
Z (%) = (Y / X) × 100 (2)
[0051]
The layered silicate dispersed in the polyimide resin composition has an average interlayer distance of the (001) plane measured by a wide-angle X-ray diffraction measurement method of preferably 3 nm or more, more preferably 3 to 5 nm. . The average interlayer distance of the layered silicate means the average of the distance between the layers when the flaky crystal of the layered silicate is regarded as a layer, and indicates an X-ray diffraction peak and a wide-angle X-ray such as a transmission electron microscope image. This is a distance calculated by a diffraction measurement method.
When the average interlayer distance exceeds 5 nm, the flaky crystals of the layered silicate are separated for each layer and the interaction of the layered silicate is weakened to a negligible degree, so that the polyimide resin composition exhibits a low coefficient of thermal expansion. It becomes difficult.
[0052]
Further, the average interlayer distance of the layered silicate is 3 to 5 nm, and part or all of the layered silicate is dispersed as a laminate of 5 layers or less, whereby the interface between the polyimide resin composition and the layered silicate is reduced. The area can be made sufficiently large. Therefore, since the polyimide resin composition of the present invention has a high melt viscosity, the thermoformability such as hot pressing, embossing, embossing, etc. can be improved, and the retention of the thermoformed shape can be improved.
[0053]
Further, the layered silicate contained in the polyimide resin composition can be sintered at the time of combustion to form a flame-retardant film and exhibit high flame retardancy. This flame-retardant film is formed at an early stage of combustion, and can cut off supply of oxygen from the outside world and also cut off combustible gas generated by combustion.
[0054]
Further, the polyimide resin composition of the present invention can enhance the barrier property against water molecules and gas molecules by containing the layered silicate. That is, by containing the layered silicate as a solid material in the resin, the solid molecules can prevent the diffusion of water molecules and gas molecules, and can prevent the water molecules and gas molecules from diffusing into the resin composition. it can.
Similarly, by containing a solid substance such as a layered silicate, the barrier property against water molecules and gas molecules is also improved, and the solvent resistance, moisture absorption resistance, water absorption resistance, and the like are improved. Accordingly, the polyimide resin composition of the present invention can exhibit high connection reliability by absorbing water molecules and gas molecules, thereby preventing a decrease in insulating properties.
[0055]
Further, in the polyimide resin composition of the present invention, the layered silicate is dispersed in a fine state, so that when a substrate or the like made of the resin composition is subjected to perforation processing, the inner wall of the perforation is highly smooth. Can have a degree.
As a specific example, when a substrate made of a resin composition is subjected to perforation processing using a laser such as a carbon dioxide gas laser, the resin component and the layered silicate component are simultaneously decomposed and evaporated by the laser, and partially remain on the inner wall of the perforation. Since only a small layered silicate residue of several μm or less is formed, the perforation can be performed with the inner wall being smooth. Thereby, it is possible to prevent the occurrence of plating failure or the like due to the residue generated by the perforation processing.
[0056]
The temperature at which tan δ of the polyimide resin composition of the present invention exhibits a peak (hereinafter, the peak temperature of tan δ) is an essential requirement that it be in a temperature range from 0 ° C to the glass transition temperature of the polyimide resin alone.
[0057]
In addition, in this specification, the glass transition temperature means a temperature at which the coefficient of thermal expansion changes abruptly when shifting from a supercooled state to a glassy state.
Further, tan δ is a value called a mechanical loss tangent in dynamic viscoelasticity measurement by, for example, tensile shear stress.
[0058]
Further, the tan δ peak temperature is generally related to the degree of freedom of the molecular chain motion of the polyimide resin, and a high tan δ peak temperature means that the degree of freedom of the molecular chain motion is low. Therefore, the peak temperature of the polyimide resin increases when the molecular chain motion of the polyimide resin is inhibited by the layered silicate or the like, and the degree of the increase in the peak temperature increases as the layered silicate is dispersed in a finer state. .
[0059]
Similarly, the value of tan δ at the peak temperature of tan δ is related to the degree of freedom of the molecular chain motion of the polyimide resin, and a small value of tan δ at the peak temperature means that the degree of freedom of the molecular chain motion is low. are doing. Therefore, the value of tan δ at the peak temperature of the polyimide resin decreases when the molecular chain motion of the polyimide resin is inhibited by the layered silicate or the like, and the tan δ at the peak temperature as the layered silicate is dispersed in a finer state. The degree of decrease in the value increases.
[0060]
The tan δ peak temperature of the polyimide resin composition of the present invention is an essential requirement that the tan δ peak temperature of only the polyimide resin not containing the layered silicate be 30 ° C or higher, preferably 35 ° C or higher, It is more preferable that the temperature is 40 ° C. or higher.
This indicates that the polyimide resin composition of the present invention has sufficiently fine layered silicate dispersed therein to greatly inhibit the molecular chain motion of the polyimide resin composition. On the other hand, a low water absorption rate and a low thermal expansion coefficient can be exhibited, and a decrease in insulation due to moisture absorption can be prevented, and high connection reliability can be exhibited even in a high humidity environment.
[0061]
Further, the peak temperature of tan δ of the polyimide resin composition of the present invention is preferably 1.2 times or more, and more preferably 1.25 times or more of the tan δ peak temperature of only the polyimide resin containing no layered silicate. Is more preferably 1.3 times or more.
In the present specification, the peak temperature of tan δ is shown in degrees Celsius (° C.). The above description is based on, for example, the case where the peak temperature of tan δ of only the polyimide resin is 70 ° C. The peak temperature is 84 ° C. or higher, which is 1.2 times or more the peak temperature.
[0062]
This indicates that the polyimide resin composition of the present invention has sufficiently fine layered silicate dispersed therein to greatly inhibit the molecular chain motion of the polyimide resin composition. On the other hand, a low water absorption rate and a low thermal expansion coefficient can be exhibited, and a decrease in insulation due to moisture absorption can be prevented, and high connection reliability can be exhibited even in a high humidity environment.
[0063]
Further, at the peak temperature of tan δ of the polyimide resin composition of the present invention, the value of tan δ of the polyimide resin composition is preferably 0.7 times or less the value of tan δ of only the polyimide resin containing no layered silicate. , 0.65 times or less, and more preferably 0.6 times or less.
[0064]
This indicates that the polyimide resin composition of the present invention has sufficiently fine layered silicate dispersed therein to greatly inhibit the molecular chain motion of the polyimide resin composition. On the other hand, a low water absorption rate and a low thermal expansion coefficient can be exhibited, and a decrease in insulation due to moisture absorption can be prevented, and high connection reliability can be exhibited even in a high humidity environment.
[0065]
The coefficient of thermal expansion of the polyimide resin composition of the present invention is preferably 50 ppm / ° C or lower, more preferably 40 ppm / ° C or lower, and more preferably 30 ppm / ° C or lower in a temperature range of 100 to 200 ° C. More preferred. When the coefficient of thermal expansion is 50 ppm / ° C. or less, shape stability can be maintained even at a high temperature, and high connection reliability can be exhibited.
[0066]
The average coefficient of thermal expansion of the polyimide resin composition of the present invention can be measured by a known method according to JIS K7197. For example, a TMA (Thermomechanical Analysis) device (manufactured by Seiko Electronics Co., Ltd., TMA / SS120C) can be used. Using a test piece of about 4 mm × 23.6 mm and a thickness of 50 μm, 5 × 10 ⁴ It can be obtained by raising the temperature at a rate of 5 ° C./min with a tensile load of Pa.
[0067]
Further, the polyimide resin composition of the present invention preferably has a water absorption defined by the following formula (3) of 1.5% or less, more preferably 1.0% or less, and more preferably 0.5% or less. It is more preferred that:
When the water absorption of the polyimide resin composition is 1.5% or less, it is possible to prevent a decrease in insulation due to the polyimide resin composition absorbing water in the air, and to achieve a high connection even in a high humidity environment. Reliability can be demonstrated.
[0068]
(Water absorption) = (weight after water absorption−weight before water absorption) / (weight before water absorption) × 100 (3)
[0069]
In addition, the polyimide resin composition of the present invention may contain, if necessary, additives such as a flame retardant, a nucleating agent, an antioxidant (antioxidant), a heat stabilizer, and a light stabilizer as long as the performance is not hindered. Agents, ultraviolet absorbers, lubricants, flame retardant aids, antistatic agents, antifogging agents, fillers, softeners, plasticizers, coloring agents, and the like may be added. These may be used alone or in combination of two or more.
[0070]
Examples of the flame retardant, which is one of the additives, include a metal hydroxide, a metal oxide, a phosphorus compound, a nitrogen compound, a fluororesin, a silicone oil, and a layered double hydrate. These flame retardants may be used alone or in combination of two or more.
[0071]
The flame retardant, which is one of the additives, is preferably a flame retardant containing no halogen-based composition. It is to be noted that a small amount of halogen may be mixed due to the production process of the flame retardant or the like.
[0072]
Examples of the metal hydroxide include aluminum hydroxide, magnesium hydroxide, dawsonite, calcium aluminate, gypsum gypsum, calcium hydroxide and the like.
Examples of the phosphorus compound include red phosphorus, ammonium polyphosphate and the like.
Examples of the nitrogen-based compound include melamine, melamine cyanurate, melamine isocyanurate, melamine phosphate, and melamine derivatives obtained by subjecting these to surface treatment.
Examples of the layered double hydrate include hydrotalcite and the like.
[0073]
Among these flame retardants, metal hydroxides and melamine derivatives are preferably used. Further, among the metal hydroxides, magnesium hydroxide and aluminum hydroxide are more preferably used, and these may be subjected to surface treatment with various surface treatment agents.
Examples of such a surface treatment agent include a silane coupling agent, a titanate coupling agent, a PVA surface treatment agent, and an epoxy surface treatment agent.
[0074]
The content of the flame retardant is preferably from 0.1 to 100 parts by weight, more preferably from 5 to 80 parts by weight, further preferably from 10 to 70 parts by weight, based on 100 parts by weight of the polyimide resin. preferable. When the content of the flame retardant is within this range, the polyimide resin composition of the present invention can exhibit sufficient flame retardancy without adversely affecting mechanical properties, electrical properties, process suitability, and the like.
[0075]
The method for producing the polyimide resin composition of the present invention is not particularly limited, and examples include a direct kneading method, a solvent removing method, a method by polymerization, and the like.
[0076]
The direct kneading method is, for example, a method of directly mixing and kneading a predetermined amount of each of the polyimide resin and the layered silicate with a predetermined amount of an additive or the like added as needed.
[0077]
The solvent removal method is, for example, adding a polyimide resin, a layered silicate, and predetermined amounts of additives and the like added as necessary to a solvent such as N-methyl-2-pyrrolidone and dimethylformamide and mixing them. Then, the solvent is removed.
[0078]
The method by polymerization is a method of kneading a predetermined amount of each of a polyimide resin monomer, a layered silicate, and an additive to be added as necessary, and polymerizing the monomer to polymerize the polyimide resin and produce a polyimide resin composition. This is a method that is performed simultaneously and collectively. When the monomer is polymerized, it is preferable to previously contain a polymerization catalyst such as a transition metal complex as a polymerization initiator.
[0079]
Known methods can be used as a method of kneading or mixing a resin or the like in a solvent when producing the polyimide resin composition of the present invention, for example, an extruder, a two-roller, a kneader such as a Banbury mixer. And kneading or mixing in a solvent.
[0080]
Although the use of the polyimide resin composition of the present invention is not particularly limited, it may be dissolved in an appropriate solvent, or formed into a film and processed, for example, by utilizing a low water absorption and a low coefficient of thermal expansion. Can be used as a resin sheet. Note that the sheet means a planar material, and includes a film-like material.
Resin sheets include materials for wiring boards such as multilayer printed boards and build-up boards, sealing films, laminates, copper foil with resin, copper-clad laminates, TAB films, printed boards, prepregs, varnishes, and optical waveguide materials. And the like. A resin sheet using these polyimide resin compositions is also one of the present invention.
[0081]
【Example】
Hereinafter, the present invention will be described in more detail with reference to Examples, but the present invention is not limited to these Examples.
[0082]
(Example 1)
A plate-like molded body was produced by the following method.
First, the following polyimide resin monomer was added to and dissolved in 41 parts by weight of N-methyl-2-pyrrolidone as a solvent, and the mixture was uniformly stirred at a stirring speed of 150 rpm for 3 hours using a stirrer. A monomer solution was obtained.
-Pyromellitic anhydride 3.0171 parts by weight
Bis [4 (3-aminophenoxy) phenyl] sulfone 5.9829 parts by weight
[0083]
Next, as a layered silicate, 0.45 parts by weight of hectorite (“Lucentite STN” manufactured by Corp Chemical Co., Ltd.) swollen between layers with trioctylmethylammonium chloride was added to N-methyl-2-pyrrolidone as a solvent. It was added to 8.55 parts by weight, dissolved, and uniformly stirred for 1 hour at a stirring speed of 300 rpm using a stirrer to obtain a layered silicate solution.
[0084]
Thereafter, 50 parts by weight of the monomer solution for polyimide resin obtained from the above operation and 9 parts by weight of the layered silicate solution were mixed, and the mixture was stirred for 2 hours at a stirring speed of 300 rpm using a stirrer. And a layered silicate mixed solution was obtained.
[0085]
After applying the obtained mixed solution on a sheet of polyethylene terephthalate (PET) using an applicator, the mixed solution was heated at 100 ° C for 1 hour, 150 ° C for 1 hour, and 200 ° C for 1 hour under a nitrogen atmosphere. The solvent was removed by sequentially heating. Thereafter, by heating in a nitrogen atmosphere at 250 ° C. for 30 minutes, at 300 ° C. for 30 minutes, and at 350 ° C. for 30 minutes, the polyimide resin monomer was polymerized to prepare a 50 μm-thick plate-shaped molded body. .
[0086]
(Example 2)
Hectorite in which the layered silicate used in Example 1 is swollen between layers with 1,2-dimethyl-N-decylimidazolium (“Lucentite SWN”, manufactured by Corp Chemical: cation exchange capacity 71 meq / 100 g) 0 A plate-like molded body was produced in the same manner as in Example 1 except that the amount was 0.45 parts by weight.
[0087]
(Example 3)
Example 1 Except that the layered silicate used in Example 1 was 0.45 parts by weight of hectorite (“Lucentite STN-A” manufactured by Corp Chemical Co.) swollen between layers with trioctylmethylammonium chloride. In the same manner as in Example 1, a plate-like molded body was produced.
[0088]
(Comparative Example 1)
By the following method, a polyimide resin in the resin composition in Example 1 was synthesized to produce a plate-like molded body.
First, the following polyimide resin monomer was added to and dissolved in 41 parts by weight of N-methyl-2-pyrrolidone as a solvent, and the mixture was uniformly stirred at a stirring speed of 150 rpm for 5 hours using a stirrer. A monomer solution was obtained.
-Pyromellitic anhydride 3.0171 parts by weight
Bis [4 (3-aminophenoxy) phenyl] sulfone 5.9829 parts by weight
[0089]
After applying the obtained monomer solution for polyimide resin to a sheet of polyethylene terephthalate (PET) using an applicator, the mixed solution was heated at 100 ° C for 1 hour, 150 ° C for 1 hour, and 200 ° C under a nitrogen atmosphere. The solvent was removed by heating for 1 hour. Thereafter, by heating in a nitrogen atmosphere at 250 ° C. for 30 minutes, at 300 ° C. for 30 minutes, and at 350 ° C. for 30 minutes, the polyimide resin monomer was polymerized to prepare a 50 μm-thick plate-shaped molded body. .
[0090]
(Comparative Example 2)
Except that the layered silicate used in Example 1 was 0.45 parts by weight of hectorite (“Lucentite SWN” manufactured by Coop Chemical Co., Ltd.) in which the interlayer was not swollen, the plate-like silicate was formed in the same manner as in Example 1. A molded body was produced.
[0091]
The plate-shaped molded bodies having a thickness of 50 μm and 100 mm obtained in the above Examples and Comparative Examples were cut into 4 mm × 23.6 mm, respectively, and the test pieces were measured or evaluated according to the following methods. .
[0092]
(Measurement of tan δ peak temperature and glass transition temperature)
Using a viscoelasticity measuring device (Rheometric Scientific RSAII), the temperature at which tan δ peaks and the glass transition temperature of the test piece were measured at a heating rate of 5 ° C./min.
The measured temperature range was from 0 ° C. to 300 ° C. When two or more tan δ peaks were observed in this temperature range, the temperature at which the value of tan δ was the largest was read.
[0093]
A temperature difference was calculated by subtracting the tan δ peak temperature of the test piece obtained in Comparative Example 1 from the tan δ peak temperature of the test piece.
[0094]
Further, a ratio was calculated by dividing the tan δ peak temperature of the test piece by the tan δ peak temperature of the test piece obtained in Comparative Example 1.
[0095]
Further, at each peak temperature of tan δ of the test piece, a value was calculated by dividing the value of tan δ by the value of tan δ of the test piece obtained in Comparative Example 1 at each peak temperature.
[0096]
(Measurement of water absorption)
First, the weight of the test piece when the test piece was dried at 350 ° C. for 30 minutes was measured, and then the weight of the test piece after being immersed in water at 23 ° C. for 24 hours was measured. ) Was used to measure the water absorption (unit:%) of the test piece.
[0097]
(Water absorption) = (weight after water absorption−weight before water absorption) / (weight before water absorption) × 100 (4)
[0098]
(Measurement of thermal expansion coefficient)
The average thermal expansion coefficient of the test piece was measured by a method according to JIS 7197 using a TMA (Thermomechanical Analysis) device (“TMA / SS120C” manufactured by Seiko Instruments Inc.). In addition, as a measurement condition, the tensile load per unit sectional area is 5 × 10 ⁴ Pa, the measurement temperature range was 100 to 200 ° C, and the heating rate was 5 ° C / min.
[0099]
Table 1 shows the results of each measurement.
[0100]
[Table 1]

[0101]
【The invention's effect】
Since the polyimide resin composition of the present invention is excellent in low water absorption and low thermal expansion coefficient, it can prevent disconnection or the like due to a decrease in insulating property or thermal expansion, and can exhibit high connection reliability. .
In addition, since the substrate material of the present invention is composed of the polyimide resin composition of the present invention, it is excellent in low water absorption and low thermal expansion coefficient, and prevents disconnection or the like due to a decrease in insulating property or thermal expansion. Therefore, high connection reliability can be exhibited.

Claims (6)

A polyimide resin composition containing a layered silicate swollen with an interlayer organic compound in the polyimide resin,
The peak temperature of tan δ in the dynamic viscoelasticity measurement by the tensile shear stress of the polyimide resin composition is in a temperature range from 0 ° C. to the glass transition temperature of the polyimide resin, and is higher than the tan δ peak temperature of the polyimide resin. A temperature higher than 30 ° C. A polyimide resin composition containing a layered silicate swollen with an interlayer organic compound in the polyimide resin,
The peak temperature of tan δ in the dynamic viscoelasticity measurement by the tensile shear stress of the polyimide resin composition exists in a temperature range from 0 ° C. to the glass transition temperature of the polyimide resin or lower, and the peak temperature of tan δ of the polyimide resin is A polyimide resin composition characterized by being 1.2 times or more. A polyimide resin composition containing a layered silicate swollen with an interlayer organic compound in the polyimide resin,
The peak temperature of tan δ in the dynamic viscoelasticity measurement by tensile shear stress of the polyimide resin composition exists in a temperature range from 0 ° C. to a glass transition temperature of the polyimide resin,
A polyimide resin composition, wherein the tan δ peak intensity of the polyimide resin composition is 0.7 times or less the tan δ peak intensity of the polyimide resin. The polyimide resin composition according to any one of claims 1 to 3, wherein the polyimide resin has thermoplasticity. The polyimide resin composition according to any one of claims 1 to 3, wherein the layered silicate is at least one selected from montmorillonite, hectorite, saponite, swellable mica, and vermiculite. A resin sheet comprising the polyimide resin composition according to claim 1.